$\dfrac{5}{10} - \dfrac{3}{10} = {?}$
Solution: $ = {\dfrac{5 \times 1}{10 \times 1}} - {\dfrac{3 \times 1}{10 \times 1}} $ $ = {\dfrac{5}{10}} - {\dfrac{3}{10}} $ $ = \dfrac{{5} - {3}}{10} $ $ = \dfrac{2}{10}$